1. Technical Field
This invention relates generally to materials for constructing buildings and structures and more specifically to roof panels used to form a roof of a building or structure.
2. State of the Art
Buildings have historically been constructed of brick, cement block, wood frame and, more recently, steel frame and stucco. The material and techniques used in constructing buildings is evolving in an effort to reduce cost, increase energy efficiency, reduce the amount of wood usage in buildings, and to reduce material waste. Cement block and brick construction requires a large amount of manpower to create a building, which raises the cost of the building. Wood has long been a staple material in building construction, but recently there is a desire to preserve forest resources. Wood is inherently more susceptible to damage from inclement weather, moisture, mold, fire, and insect infestation. Also, when wood is used to create a building there can be a large amount of waste. This is because standard sized boards are sent to the construction site, which must be cut and assembled at the building site into a building. The labor involved in cutting lumber to size results in high labor costs and a large amount of lumber wasted from boards cut to size.
It is also desirable to increase the energy efficiency of buildings in order to reduce the energy costs during the lifetime of the building. Cement block, brick, and wood frame and stucco construction do not provide the high level of energy efficiency that can be obtained from newer materials.
Foam blocks have become a popular alternative and are environmentally sustainable as compared to traditional wood, cement block, and brick construction materials. Foam block systems are lightweight, can be molded or formed into any needed shape, result in a thermally efficient building construction, and require less skilled manpower to form into a building structure. Other benefits include, but are not limited to, a resistance to moisture, mold, fire and insect damage. The foam blocks are constructed using materials which are recyclable and renewable, provide good insulating qualities, and are often themselves made from recycled materials. Alternatively, construction blocks can also be made from other environmentally friendly materials such as straw, wood fibers, paper, and glass, for example.
One problem with some of the new building materials such as foam block is that the structural strength of a building element that is made with foam blocks may not be as high as when wood, brick or cement block are used to form the building element. This can be particularly important in areas where buildings are required to withstand high winds or earthquakes. There is a need for a building panel system which minimizes construction time, uses environmentally friendly materials, and results in a building with high structural strength and structural integrity.
The roof of a building or structure is of particular importance to the energy consumption of the complete building. When the heat transfer through the roof of a building is minimized, the energy efficiency of the whole building can be maximized. Thus there is a need for composite building panels specifically designed for use in the roof of a building.